The effects of whole-body vibration training on knee function and physical performance of middle-aged and elderly woman with knee osteoarthritis and chronic knee pain

Abstract

The purpose of this study was to elucidate the effects of whole-body vibration training (WBVT) on knee function and physical performance in middle-aged and older Japanese women who suffered from knee osteoarthritis (OA) and knee pain. Thirty-eight middle-aged and older Japanese women (aged 50-73 years) with knee OA and knee pain were divided into twogroups: (1) a WBVT group (n = 29) engaging in WBVT 3 times a week for 8 weeks, and (2) a control group (C group, n = 9) performing exercises at home. The WBVT program consisted of a warm-up, strength training mainly of the quadriceps and their surrounding muscles and cool-down exercises. In the WBVT group, there were no dropouts, and there were significant improvements in the physical function (Cohen's d = 0.28) and total score (Cohen's d = 0.25) of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). There were also statistically significant improvements in all lower-extremity function tests (5-times sit-to-stand, timed up and go, standing time from a long sitting position, sit and reach, 4-way choice reaction time; Cohen's d = 0.34-1.24). The item that changed significantly in the C group, however, was only the sit and reach (Cohen's d = 0.52). In addition, all items in the Japanese Orthopaedic Association Score (JOA score) improved significantly (Cohen's d = 0.63-0.67) in the WBVT group. In conclusion, the 8-week WBVT program can safely improve knee function and physical performance in middle-aged and older Japanese women who suffer from knee OA and knee pain.